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Near-wall velocity measurements by Particle-Shadow-Tracking  [PDF]
Pierre Lancien,Eric Lajeunesse,Fran?ois Métivier
Physics , 2007, DOI: 10.1007/s00348-007-0260-z
Abstract: We report a new method to measure the velocity of a fluid in the vicinity of a wall. The method, that we call Particle-Shadow Tracking (PST), simply consists in seeding the fluid with a small number of fine tracer particles of density close to that of the fluid. The position of each particle and of its shadow on the wall are then tracked simultaneously, allowing one to accurately determine the distance separating tracers from the wall and therefore to extract the velocity field. We present an application of the method to the determination of the velocity profile inside a laminar density current flowing along an inclined plane.
Shadow on the wall cast by an Abrikosov vortex  [PDF]
S. Graser,C. Iniotakis,T. Dahm,N. Schopohl
Physics , 2004, DOI: 10.1103/PhysRevLett.93.247001
Abstract: At the surface of a d-wave superconductor, a zero-energy peak in the quasiparticle spectrum can be observed. This peak appears due to Andreev bound states and is maximal if the nodal direction of the d-wave pairing potential is perpendicular to the boundary. We examine the effect of a single Abrikosov vortex in front of a reflecting boundary on the zero-energy density of states. We can clearly see a splitting of the low-energy peak and therefore a suppression of the zero-energy density of states in a shadow-like region extending from the vortex to the boundary. This effect is stable for different models of the single Abrikosov vortex, for different mean free paths and also for different distances between the vortex center and the boundary. This observation promises to have also a substantial influence on the differential conductance and the tunneling characteristics for low excitation energies.
Supersymmetry Breakdown at a Hidden Wall  [PDF]
H. P. Nilles,M. Olechowski,M. Yamaguchi
Physics , 1998, DOI: 10.1016/S0550-3213(98)00418-0
Abstract: We consider hidden sector supersymmetry breakdown in the strongly coupled heterotic $E_8\times E_8$ theory of Ho\v{r}ava and Witten. Using effective field theory methods in four dimensions, we can show that gravitational interactions induce soft breaking terms in the observable sector that are of order of the gravitiono mass. We apply these methods to the mechanism of gaugino condensation at the hidden wall. Although the situation is very similar to the weakly coupled case, there is a decisive difference concerning the observable sector gaugino mass; with desirable phenomenological as well as cosmological consequences.
Shadow multiplets in AdS_4/CFT_3 and the super-Higgs mechanism: hints of new shadow supergravities  [PDF]
M. Billo`,D. Fabbri,P. Fre`,P. Merlatti,A. Zaffaroni
Physics , 2000, DOI: 10.1016/S0550-3213(00)00532-0
Abstract: We discuss a general pairing that occurs in compactifications of M-theory on AdS_4 x X^7 backgrounds between massless ultra short multiplets and their massive shadows, namely certain universal long multiplets with fixed protected dimensions. In particular we consider the shadow of the short graviton multiplet in N=3 compactifications. It turns out to be a massive spin 3/2 multiplet with scale dimension E_0=3 and with the quantum numbers of a super-Higgs multiplet. Hence each N=3 AdS_4 x X^7 vacuum is actually to be interpreted as a spontaneously broken phase of an N=4 theory. Comparison with standard gauged N=4 supergravity in 4 dimensions reveals the unexpected bound E_0<3 on the dimension of the broken gravitino multiplet. This hints to the existence of new versions of extended supergravities, in particular N=4 where such upper bounds are evaded and where all possible vacua have a reduced supersymmetry N_0
Diffraction 2000: New Scaling Laws in Shadow Dynamics  [PDF]
A. A. Arkhipov
Physics , 2000, DOI: 10.1016/S0920-5632(01)01311-1
Abstract: New scaling structure for the shadow corrections in elastic scattering from deuteron at high energies has been presented and discussed. It is shown that this structure corresponds to the experimental data on proton(antiproton)-deuteron total cross sections. The effect of weakening for the inelastic screening at superhigh energies has been theoretically predicted.
Shadow Higgs from a scale-invariant hidden $U(1)_s$ model
Chang, We-Fu;Ng, John N.;Wu, Jackson M. S.
High Energy Physics - Phenomenology , 2007, DOI: 10.1103/PhysRevD.75.115016
Abstract: We study a scale invariant $SU(2)\times U(1)_Y \times U(1)_s$ model which has only dimensionless couplings. The shadow $U(1)_s$ is hidden, and it interacts with the Standard Model (SM) solely through mixing in the scalar sector and kinetic mixing of the U(1) gauge bosons. The gauge symmetries are broken radiatively by the Coleman-Weinberg mechanism. Lifting of the flat direction results in a light shadow Higgs or "scalon", and a heavier scalar which we identify as the SM Higgs boson. The phenomenology of this model is discussed. It is possible that shadow Higgs boson can be discovered in precision $t$-quark studies at the LHC. The conditions that it be a dark matter candidate is also discussed.
A New Shadow Removal Method for Color Images  [PDF]
Qiang He, Chee-Hung Henry Chu
Advances in Remote Sensing (ARS) , 2013, DOI: 10.4236/ars.2013.22011
Abstract:

Shadow and variable illumination considerably influence the results of image understanding such as image segmentation, object tracking, and object recognition. The intrinsic image decomposition is to separate the reflectance and the illumination image from an observed image. The intrinsic image decomposition is very useful to remove shadows and then improve the performance of image understanding. In this paper, we present a new shadow removal method based on intrinsic image decomposition on a single color image using the Fisher Linear Discriminant (FLD). Under the assumptions-Lambertian surfaces, approximately Planckian lighting, and narrowband camera sensors, there exist an invariant image, which is 1-dimensional greyscale and independent of illuminant color and intensity. The Fisher Linear Discriminant is applied to create the invariant image. And further the shadows can be removed through the difference between invariant image and original color image. The experimental results on real data show good performance of this algorithm.

The Shadow  [cached]
Lindsay Barrett
Cultural Studies Review , 2011,
Abstract: ‘The Shadow’ is a reflection on the destruction of the city of Hiroshima by an atomic bomb in 1945. It uses personal observation of the extant traces of the event in the contemporary city of Hiroshima, along with a number of historical sources, in order to understand this particular catastrophe as part of the wider experience of modernity in the twentieth century.
Shadow networks: Discovering hidden nodes with models of information flow  [PDF]
James P. Bagrow,Suma Desu,Morgan R. Frank,Narine Manukyan,Lewis Mitchell,Andrew Reagan,Eric E. Bloedorn,Lashon B. Booker,Luther K. Branting,Michael J. Smith,Brian F. Tivnan,Christopher M. Danforth,Peter S. Dodds,Joshua C. Bongard
Computer Science , 2013,
Abstract: Complex, dynamic networks underlie many systems, and understanding these networks is the concern of a great span of important scientific and engineering problems. Quantitative description is crucial for this understanding yet, due to a range of measurement problems, many real network datasets are incomplete. Here we explore how accidentally missing or deliberately hidden nodes may be detected in networks by the effect of their absence on predictions of the speed with which information flows through the network. We use Symbolic Regression (SR) to learn models relating information flow to network topology. These models show localized, systematic, and non-random discrepancies when applied to test networks with intentionally masked nodes, demonstrating the ability to detect the presence of missing nodes and where in the network those nodes are likely to reside.
New Regularization Using Domain Wall  [PDF]
Shoichi Ichinose
Physics , 1999, DOI: 10.1016/S0550-3213(00)00037-7
Abstract: We present a new regularization method, for d dim (Euclidean) quantum field theories in the continuum formalism, based on the domain wall configuration in (1+d) dim space-time. It is inspired by the recent progress in the chiral fermions on the lattice. The wall "height" is given by 1/M, where M is a regularization mass parameter and appears as a 1+d dim Dirac fermion mass. The present approach gives a thermodynamic view to the domain wall or the overlap formalism in the lattice field theory. We will show qualitative correspondence between the present continuum results and those of the lattice. The extra dimension is regarded as the (inverse) temperature t. The domains are defined by the directions of the "system movement", not by the sign of M as in the original overlap formalism. Physically the parameter M controls both the chirality selection and the dimensional reduction to d dimension. From the point of regularization, the limit $Mt\ra 0$ regularize the infra-red behaviour whereas the condition on the momentum ($k^\m$) integral, $|k^\m|\leq M$, regularize the ultra-violet behaviour. To check the new regularization works correctly, we take the 4 dim QED and 2 dim chiral gauge theory as examples. Especially the consistent and covariant anomalies are correctly obtained. The choice of solutions of the higher dim Dirac equation characterize the two anomalies. The projective properties of the positive and negative energy free solutions are exploited in calculation. Some integral functions, the incomplete gamma functions and the generalized hypergeometric functions characteristically appear in the regularization procedure.
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